Conventional personal video recorders (PVRs) use standard personal computer file systems or modified variations of a personal computer file system. Such file systems have a number of disadvantages when used in a personal video recorder. First, such file systems have irregular data transfer rates. In particular, the file system management overheads can cause the data transfer rate to be irregular and/or non-deterministic. Second, data transfer rates are not homogeneous. For example, the data transfer rate depends on the direction of the streaming such that files streamed backwards have a poorer data transfer rate than those streamed forwards. Conventional PVRs often implement a large memory cache to mitigate this problem. Third, personal computer file systems use time consuming recovery algorithms. In particular, general personal computer file systems have expensive recovery algorithms that are used when there is an unexpected power outage.
Therefore, conventional general purpose file systems do not adequately address the needs of applications that (i) use high streaming data transfer rates and (ii) operate in a harsh consumer environment.
It would be desirable to implement an embedded personal video recording product that uses storage space provided by a storage device that (i) is managed efficiently, (ii) is managed in a way suitable for a consumer product, (iii) is implemented with a recoverable streaming file system and/or (iv) minimizes overheads (i.e., seeks).